This shot is actually incredibly simple but does require some knowledge of colour temperature. The main light from the right is a 80'' octabox with grid in another room. No flash was used, only the warm modelling light. As it was dusk, I wanted to mix the ambient light from the window behind Lucy with the key light from the octabox. The strobe would have been too blue and made the overall colour a lot more flat. Keeping it with the modelling light only, gave me a contrast with the ambient being blue and the key light warming Lucy up. The trade off is that I needed to shoot at a high ISO, in this case 1600.

Before and After Post-Processing

As you can see from the before and after above, there isn't a huge amount of changes done to the image. I removed the smoke detector from the ceiling and some lines from the walls. I tone down the purple and contrast slightly and selectively sharpened Lucy. Lastly I reshaped the ceiling slightly so it's no so tilted. The actual building is completely skewed, but that is the charm of older buildings.